Computer users have grown accustomed to user-friendly software applications that help them write, calculate, organize, prepare presentations, send and receive electronic mail, make music, and the like. For example, word processing applications allow users to prepare a variety of useful documents. Spreadsheet applications allow users to enter, manipulate, and organize data. Slide presentation applications allow users to create a variety of slide presentations containing text, pictures, data or other useful objects.
Documents created by such applications (e.g. word processing documents, spreadsheets, slide presentation documents), however, have a limited facility for storing/transporting the contents of arbitrary metadata required by the context of the documents. For example, a solution built on top of a word processing document may require the storage of workflow data that describes various states of the document, for example, previous workflow approval states (dates, times, names), current approval states, future workflow states before completion, name and office address of document author, document changes, and the like. The options for storing this information are primarily limited to the use of document variables or existing custom object linking and embedding (OLE) document properties that have limitations. For example, hierarchical data may not be stored; character length is limited, and the like. The properties for such methods are stored in a single store, for example, an OLE properties store, which means the properties have a possibility of conflicting. Further, such stored properties have no data validation. It is difficult for users of such applications and related documents to store arbitrary data with documents, which is a common need of many users.